Method and installation for pumping liquid to any desired level



INVENTOR ATTORNEYS A. VENTRESS Q l I '1? N Y A DOUGLAS ARTHUR VENTRESS D. METHOD AND INSTALLATION FOR PUMPING LIQUID TO ANY DESIRED LEVEL Filed D60. 28, 1959 June 11, 1963 kin United States Patent Oil ice 3,093,088 Patented June 11, 1963 3,093,088 METHOD AND INSTALLATION FOR PUMPING LIQUID TO ANY DESIRED LEVEL Douglas Arthur Veutress, Winkley St, Berea, East London, Cape Province, Republic of South Africa Filed Dec. 28, 1959, Ser. No. 862,257 Claims priority, application Republic of South Africa Jan. 20, 1959 12 Claims. (Cl. 103-432) The present invention relates to a method and installation for pumping liquid.

It is an object of the invention to provide a new or improved method and means for pumping liquid to any desired level.

A further object of the invention is the provision of a method and means for pumping liquid from bore holes and similar difficulty accessible places, involving a minimum of moving parts in those places.

One advantage of the invention is that it avoids the use of complicated mechanical parts in contact with the liquid and is therefore very well suited to the pumping of corrosive liquids, e.g. in chemical processes.

Further objects, advantages and applications of the invention will become apparent from the following description.

A method for pumping liquid to any desired level in accordance with the invention comprises submerging the lower end of a pipe or similar conduit in the liquid to be pumped, applying suction to the upper end of the tube or the like, withdrawing the pipe above the level of said liquid to be pumped as soon as a column of liquid has been drawn into the pipe or the like which has the desired length, but the vertical length of which is less, than the maximum column length which could be supported in a barometric tube by the atmospheric or other pressure prevailing in the gas space above the level of the liquid to be pumped, and which further comprises drawing the said column of liquid after its isolation from the liquid to be pumped through the pipe up to the desired height.

In the preferred method, the liquid is allowed to run into a collecting vessel or the like after it has been drawn to the required height. The above-mentioned cycle of operations may be repeated as many times as necessary to pump a given amount of liquid to a higher level.

Preferably the said tube or the like is not raised and lowered as a whole but is provided with an end portion which is movably connected thereto, preferably in a telescopic manner, and which is raised and lowered while the main portion of the tube remain stationary. The said pulse-like raising and lowering of the end of the pipe may be effected by automatic means. In the preferred method, the suction is applied continually during the reciprocating movement of the lower end of the pipe.

In one preferred embodiment of the invention the lowering movement of the pipe end is elleoted by #2111 actuating device which is triggered when the lower end of the said column of liquid passes the desired level to which the liquid is pumped. The actuating device may be an electric relay which controls .a hydraulic winch gear.

According to an alternative method, the upper end of a rising column of liquid triggers an actuating device which then causes the pipe end to be lowered into the liquid in the reservoir.

The lengths of the column to be sucked up with every pulse may be determined by similar means or by the length of time during which the pipe end is submerged, or in any other suitable manner.

The means for carrying out the method specified above comprise a pipe or similar conduit, the lower end of which is adapted to alternately be submerged below and 2 raised above the level of liquid in a storage vessel, res-ervo ir, bore hole or other source, means for bringing about this raising or lowering, with such timing that the total vertical length of the column or columns of liquid in the pipe at any stage of the pumping cycle is less than the maximum column length which could be supported in a barometric tube by the atmospheric or other pressure prevailing in the gas space above the level of the liquid to be pumped, a collecting vessel or equivalent connected a substantially gas-tight manner to the upper, outlet of the pipe and means for applying suction to the said collecting vessel. In the preferred embodiment, the lower part of the said pipe or the like is adapted to be moved independently of the main part of the pipe, e.-g. in .a telescopic manner. For this purpose the said lower portion of the pipe may be provided with a sliding sleeve,

adapted to surround the lower end of the main part of the pipe, suitable sealing means being provided between the said sleeve and the main part of the pipe if required, e.g. in the form of a packing.

The means for bringing about the reciprocating up and down movement may comprise means for bringing these movements about automatically. Thus an 'actu'atiu'g device may be provided which is triggered when the lower or upper end of the said columnof liquid passes a certain level. The actuating device is preferably floatcontrolled, and may comprise an electric relay.

The primary source of power for the lifting and lowering mechanisrnmay be a hydraulic winch gear, which acts on the said lower portion by means of a cable. This winch gear maybe provided with a control lever which is actuated by a solenoid, which, in turn is activated by the electric relay. Spring return means may be provided to move the control lever to another position aiter a suitable time delay.

The means for applying suction may be a suction pump of any suitable kind.

The invention and the manner in which it may be put into practice will be further described by way of example with reference to the accompanying drawing without thereby limiting the scope of the invention.

The drawing represents a diagrammatic side elevation of a preferred embodiment of the invention, partly in section.

Referring to the drawing, 1 is the outer casing of a borehole provided with a cap 2. A pipe 3 leads down the borehole to a level which is a certain distance above the liquid level indicated by the horizontal dotted line. This lower portion of the pipe is surrounded by a sleeve 5, packings 6 being provided between the pipe and the sleeve. The sleeve is adapted to slide up and down with respect to the pipe 3. A further pipe section 7 isv connected to the lower end of the sleeve 5, long enough to be lowered below the liquid level before the sleeve slides beyond the lower end of the pipe 3.

One end of a cable 8 is connected to the sleeve 5. The cable passes up the borehole to a hydraulic winch gear 9, the control lever 10 of which is actuated by a solenoid 11 which in turn is actuated by a relay 12, and another solenoid 17 operating in the opposite direction when energised by a relay 18. Relay 12 is controlled by a float switch of a known construction 16.

The upper end of the pipe 3- is bent around in a syphonlike manner and passes into a vacuum collecting vessel 13, to which it is connected in a gas-tight manner. A pump 14 serves to apply suction to the vessel 13. A manual and automatic float sealing and relief valve '15 is also provided.

The winch mechanism 9 comprises a hydraulic motor 22 directly coupled to the winch drum, a hydraulic pump 23 connected by pipes to motor 22 and an electric motor 24 with starter '25. A stop 26 is provided on the winch 3 rope 8 which moves between, and actuates, low limit and high limit electric switches 19 and 20.

The installation operates as follows:

Pump 14 is started and electric motor 24 is started up with starter 25. At this stage the hydraulic motor 22 is at a standstill since springs 21 hold the operating .lever 10' of the hydraulic pump 23 in the neutral position.

Float switch 16 is now tripped by a push button (not shown) provided for this purpose whereby relay 12 is energised. Relay 12 provided with a holding coil in turn keeps solenoid 11 energised which pulls over lever 10 to cause the unwinding of the cable 8 from the winch.

Stop 26 on wire rope 8 now moves down until it engages low limit switch 19 which in turn opens the circuit of the holding coil of relay 12 while closing the circuit of the holding coil of relay 18. Accordingly solenoid 11 is de-energised and solenoid 17 is energised whereby lever 10 is pulled over to the opposite position and hydraulic motor 22 reverses to wind up the winch.

Stop 26 now moves upwards until it engages high limit switch 20, which then de-energises the holding coil of relay 18, causing solenoid 17 to release lever 10 which returns to the neutral position, thereby bringing hydraulic motor 22 to a stop.

As a result of these various steps, the pipe section 7 is lowered below the liquid level 4 while suction is applied and is then raised again. The pipe is now partly filled with liquid, however, the time delay between the lowering and raising of the pipe section is adjusted in such a manner that the liquid column is still shorter than the length which could theoretically be supported by the maximum pressure difference obtainable between the vacuum collecting vessel and the gas space above the liquid level 4.

Suction is continued while the lower pipe section is raised, as a result of which the liquid in the pipe is drawn upwards into the collecting vessel. As soon as the upper end of the column of liquid passes the float switch 16, relay 12 is again energised and the whole cycle of operations is automatically repeated.

Of course, it is also possible to replace the float switch 16 by a device in a suitable position which will be tripped when the tail end of the liquid column passes the device.

It is also possible to construct the apparatus in such a manner that when the lower end of the column of liquid passes the relay 12, the winch gear 9 is caused to unwind a length of cable to lower the pipe section 7, a spring return device on the lever 10 subsequently causes the pipe section 7 to be raised again after a short time delay.

The cycle of operations is repeated as many times as is necessary to pump up the desired amount of liquid.

It will be obvious to those skilled in the art that the method and device are operative for as long as the diameter of tubular conduit 3, 7 is maintained below the limit above which air tends to break through the liquid contained in the pipe. As will be readily appreciated this maximum diameter depends on the surface tension of the liquid being pumped, its viscosity and the crosssectional shape and wetting properties of the pipe. Since all three factors are variable within wide limits it is pointless to state upper limits for the pipe diameter, which can be readily determined, if necessary, by anyone confronted with a particular pumping problem.

What I claim is:

1. A method for pumping liquid to any desired level higher than the barometric head for the particular liquid above the level of liquid from which it is pumped, which comprises submerging the lower end of a tubular conduit of a length greater in vertical extent than said barometric head in the liquid to be pumped, applying suction to the upper end of said tubular conduit, withdrawing said lower end of the tubular conduit above the level of said liquid to be pumped as soon as a column of liquid has been drawn into the tubular conduit which has the desired length, but the vertical length of which is less than the maximum column length which could be supported in a barometric tube by the pressure prevailing in the gas space above the level of the liquid to be pumped, and drawing said column of liquid after its isolation from the liquid to be pumped through the pipe up to the desired height.

2. A method for pumping liquid as claimed in claim 1 including the step of allowing the liquid to run into a collecting vessel after it has been drawn to the required height.

3. A continuous method for pumping liquid to any desired level higher than the barometric head for the particular liquid above the level of liquid from which it is pumped, which comprises submerging the lower end of a pipe of a length greater in vertical extent than said barometric head in the liquid to be pumped, applying suction to the upper end of the pipe, withdrawing said lower end of the pipe above the level of said liquid to be pumped as soon as a column of liquid has been drawn into the pipe which has the desired length, but the vertical length of which is less than the maximum column length which could be supported in a barometric tube by the pressure prevailing in the gas space above the level of the liquid to be pumped, and drawing said column of liquid after its isolation from the liquid to be pumped through the pipe up to the desired height, and lowering the end of the pipe below the level of said liquid to be pumped and repeating this cycle of operations continuously with a pulse-like alternation of raising and lowering the pipe at a rate so controlled that the total liquid head in the pipe between the upper and lower ends thereof is always less than the maximum column length which could be supported in a barometric tube by the pressure prevailing in the gas space above the level of the liquid to be pumped with due provision for friction and velocity head losses.

4. A method for pumping liquid to any desired level as claimed in claim 3 including the step of automatically effecting the pulse-like raising and lowering of the end of the pipe.

5. A method for pumping liquid as claimed in claim 3, including the step of continually applying the suction during the repeated insertion into and withdrawal of the lower end of the pipe from the liquid in the repeated cycle of operation.

6. An apparatus for pumping liquid from a source of liquid to any desired level higher above the source than the barometric head for the particular liquid, which comprises a tubular conduit of a length greater in vertical extent than said barometric head and having an upper outlet part and a lower end, the lower end of said conduit being adapted to alternately be submerged below and raised above the level of liquid in the said source of liquid, means for effecting said alternate raising and submerging, with a controllable timing such that the total vertical length of all columns of liquid in the conduit at any stage of the pumping cycle, the plural to include the singular, is less than the maximum column length which could be supported in a barometric tube by the pressure prevailing in the gas space above the level of the liquid to be pumped, with due provision for friction and velocity head losses, at collecting vessel connected in a substantially gas-tight manner to the upper outlet part of the tubular conduit and means for applying suction to the said collecting vessel.

7. An apparatus as claimed in claim 6 in which said conduit includes a main conduit part and a lower conduit part, said main part being stationary and the said lower conduit part being vertically movable relative to the main part, the means for effecting the alternate raising and submerging of the conduit being adapted to alternately raise and lower the said lower conduit part.

8. An apparatus as claimed in claim 6 in which the said tubular conduit at its lower end terminates in a terminal tubular member in vertically slidable sealing relationship to the remainder of the tubular conduit, said means for effecting the .alternate raising and submerging of the conduit being adapted to alternately raise and lower the terminal tubular member, the remainder of the tubular conduit being stationary.

9. An apparatus for pumping liquid from a source of liquid to any desired level higher above the source than the barometric head for the particular liquid above the level of liquid from which it is pumped which comprises a tubular conduit of a length greater in vertical extent than said barometric head and having an upper outlet part and a lower end, the lower end of said conduit being adapted to alternately be submerged below and raised above the level of liquid in the said source of liquid, means for eliecting said alternate raising and submerging with a controllable timing such that the total vertical length of all columns of liquid in the conduit at any stage of the pumping cycle, the plural to include the singular, is less than the maximum column length which could be supported in a barometric tube by the pressure prevailing in the gas space above the level of the liquid to be pumped, with due provision for friction and velocity head losses, at collecting vessel connected in a substantially gas-tight manner to the upper outlet part of the tubular conduit, means for applying suction to the said collecting vessel and means for automatically controlling the above-mentioned timing.

10. An apparatus for pumping liquid from a source of liquid to any desired level higher above the source than the barometric head for the particular liquid which comprises a tubular conduit having an upper outlet part and a lower end, the lower end of said conduit being adapted to alternately be submerged below and raised above the level of liquid in the said source of liquid, means for eltecting said alternate raising and submerging with a controllable timing such that the total vertical length of all columns of liquid in the conduit at any stage of the pumping cycle, the plural to include the singular, is less than the maximum column length which could be supported in a barometric tube by the pressure prevailing in the gas space above the level of the liquid to be pumped, with due provision for friction and velocity head losses, a collecting vessel connected in a substantially gas tight manner to the upper outlet part of the tubular conduit, means for applying suction to the said collecting vessel and means for automatically controlling the above-mentioned timing by means of an actuating device adapted to be triggered when the column of liquid passes the level of the actuating device.

11. An apparatus for pumping liquid from a source of liquid to any desired level higher above the source than the barometric head for the particular liquid above the level of liquid from which it is pumped, which comprises a tubular conduit of a length greater in vertical extent than said barometric head and having an upper outlet part and a lower end, the lower end of said conduit being adapted to alternately be submerged below and raised above the level of the liquid in the said source of liquid, a hydraulic winch gear, a cable operably connecting the winch gear with said lower end for effecting the alternate raising and submerging, with such timing that the total vertical length of all columns of liquid in the conduit at any stage of the pumping cycle, the plural to include the singular, is less than the maximum column length which could be supported in a barometric tube by the pressure prevailing in the gas space above the level of the liquid to be pumped, with due provision for friction and velocity head losses, a collecting vessel connected in a substantially gas-tight manner to the upper outlet part or" the tubular conduit and means for applying suction to the said collecting vessel.

12. An apparatus as claimed in claim 11 in which the winch gear is provided with a control lever which is actuated by at least one solenoid.

References Cited in the file of this patent UNITED STATES PATENTS 248,355 Schutte Oct. 18, 1881 617,899 Krogh Jan. 17, 1889 705,670 Henson July 29, 1902 1,727,216 Porter Sept. 3, 1929 1,883,153 Watkins Oct. 18, 1932 1,985,283 Cochrane et a1 Dec. 25, 1934 FOREIGN PATENTS 487,036 Italy Nov. 20, 1953 

1. A METHOD FOR PUMPING LIQUID TO ANY DESIRED LEVEL HIGHER THAN THE BAROMETRIC HEAD FOR THE PARTICULAR LIQUID ABOVE THE LEVEL OF LIQUID FROM WHICH IT IS PUMPED, WHICH COMPRISES SUBMERGING THE LOWER END OF A TUBULAR CONDUIT OF A LENGTH GREATER IN VERTICAL EXTENT THAN SAID BAROMETRIC HEAD IN THE LIQUID TO BE PUMPED, APPLYING SUCTION TO THE UPPER END OF SAID TUBULAR CONDUIT, WITHDRAWING SAID LOWER END OF THE TUBULAR CONDUIT ABOVE THE LEVEL OF SAID LIQUID TO BE PUMPED AS SOON AS A COLUMN OF LIQUID HAS BEEN DRAWN INTO THE TUBULAR CONDUIT WHICH HAS THE DESIRED LENGTH, BUT THE VERTICAL LENGTH OF WHICH IS LESS THAN THE MAXIMUM COLUMN LENGTH WHICH COULD BE SUPPORTED IN A BAROMETRIC TUBE BY THE PRESSURE PREVAILING IN THE GAS SPACE ABOVE THE LEVEL OF THE LIQUID TO BE PUMPED, AND 